1. Field of the Invention
The invention relates generally to an apparatus and method for preventing motion sickness. The invention relates in particular to an apparatus and method for preventing motion sickness while reading in a moving vehicle by physically blocking out visual information indicative of motion.
2. Description of the Prior Art
Presently, a number of different drugs are offered for preventing motion sickness associated with travelling in a vehicle, such as a car, boat or plane. The available drugs, however, have undesirable side effects, which can be particularly hazardous if the person sensing the side effects is also operating the vehicle. In addition, drugs are inconvenient because they must be taken just prior to travel. A number of other disadvantages related to such drugs are well known.
A few products have been offered to prevent motion sickness without the use of drugs. For instance, U.S. Pat. Nos. 5,067,941 and 4,939,228 disclose an anti-motion sickness apparatus. These patents focus on alleviating motion sickness attributable to the mismatch between the motion experienced by fluid in the inner ear of the person and the vision of the person. This mismatch is caused when fluid in the inner ear senses motion, while the eyes fail to sense such motion visually. The apparatus disclosed in these patents provides a visually discernible wave motion image, such as moving liquid, which visually confirms the motion in the inner ear. This avoids the mismatch and thus prevents the motion sickness associated with it.
Another cause of motion sickness relates to the input of information to the brain stem which is interpreted as a spin. For example, when a person travelling in a moving vehicle looks forward, as one would while driving an automobile, the brain receives sufficient information to know that it is moving forward and not spinning around. However, when the eyes are focused on something inside the vehicle, such as a book, the input from peripheral vision, such as that associated with the passing of trees and telephone poles and shadows therefrom, gives the sensation of a spin, so real, that it produces a literal nystagmus (the phenomenon induced when a person is spun, wherein the eyes move back and forth in rhythmic pulses) as well as the concomitant motion sickness associated with spinning.
It would therefore be desirable to have an apparatus which prevents motion sickness associated with the visual reception of peripheral information interpreted by the brain as spinning.